Smooth tipped endotracheal tube

ABSTRACT

An endotracheal tube including a preformed inflatable plastisol balloon telescopically fitted over and secured to a forward end portion of a dual-lumen tube. The inflatable balloon is formed with an elongated forward collar which is fitted onto the duallumen tube. The tube and collar are simultaneously severed along a biased cut to provide an open front end of the endotracheal tube. The forward collar and dual-lumen tube are then fused into a generally homogeneous mass to provide a smooth exterior sliding surface at the forward end portion of the endotracheal tube.

ll ited States Patent Harautuneian 1 Jan. 28, 1975 [54] SMOOTH TIPPEI)ENDOTRACHEAL TUBE 3,734,100 5/1973 Walker 128/349 B [75} Inventor:Andrew Harautuneian, Westlake OTHER PUBLICATIONS Village Calif ShileyCuffed Trachcostomy Tube, Sept. 1970,

[73] Assignee: American Hospital Supply I I Corporation, Evdnsmnv LIrnnary IL.\'(UHIHLIAl(lHCh F. Medbery Attorney, Agent, or Firm--LurryN. Burger; Robert T.

[22] Filed: Apr. 23, 1973 Merrick [52] US. Cl. 128/351, 128/349 B [51]int. Cl A6lm 25/00 [58] Field of Search 128/349 R, 351, 349 B,

128/349 BV, 348, 2.05 R; 156/155, 294

[56] References Cited UNITED STATES PATENTS 3,292,627 12/1966Haruutuneian 128/349 B 3,304,353 2/1967 Harautuneian 261/98 3,407,81710/1968 Galleher, Jr 128/349 B 3,499,435 3/1970 Rockwell et ul. 128/3513,543,759 12/1970 MeWhorter 128/349 B X [57] ABSTRACT An endotrachealtube including a preformed inflatable plastisol balloon telescopicallyfitted over and secured to a forward end portion of a dual-lumen tube.The inflatable balloon is formed with an elongated forward collar whichis fitted onto the dual-lumen tube. The tube and collar aresimultaneously severed along a biased cut to provide an open front endof the endotracheal tube. The forward collar and dual-lumen tube arethen fused into a generally homogeneous mass to provide a smoothexterior sliding surface at the forward end portion of the endotrachealtube.

7 Claims, 5 Drawing Figures PATENTED JAN 2 8 I975 SHEET 2 OF 2 SMOOTHTIPPED ENDOTRACHEAL TUBE BACKGROUND When a patient is anesthetized withinhalable gaseous anesthesia various devices are used to direct theanesthesia into the patients lungs. One type device involves a mask thatfits over the patients nose and mouth and connects with an anesthesiamachine. Another device includes a nasal cannula where the anesthesia isdirected through the nasal passage and into the patients lungs. Stillanother, and becoming more widely used, is an endotracheal tube.

An endotracheal tube is essentially a large-diameter tube inserted inthrough the patients mouth and fed down through the trachea to where itterminates right above the bronchial branch connected to the lungs. Thisendotracheal tube is then connected to an anesthesia machine. Manyphysicians believe that the endotracheal tube method provides a moreaccurate control of administering the anesthesia to the patient.

When anesthesia is fed through the endotracheal tube in the patientstrachea a structure is required to seal the outer surface of theendotracheal tube with the trachea. This is to keep anesthesia gasesfrom escaping back between the endotracheal tube and the trachea. Acommon structure for sealing the endotracheal tube to the trachea is aninflatable balloon. This is sometimes called the cuff or tracheal ballonof an endotracheal tube. Because the endotracheal tube and balloon arein a tender area of the patients trachea it is desired that the tube andballoon be made of a nonirritating material. Previous rubber cuffs andtubes had the disadvantage of containing accelerators and vulcanizingagents, which could irritate the trachea.

Preferred endotracheal tubes are made of a thermoplastic or plastisolmaterial that do not require vulcanizing agents and cause lessirritation to the patient.

In the past these endotracheal tubes have been made by preforming aplastisol cuff or balloon and then securing this balloon to a flexibletube. One of the major problems in securing the balloon to the tubeinvolved the joint between the balloon and the tube. Because theendotracheal tube must slide down past the vocal cords it is importantto make the forward end of the endotracheal tube as smooth as possible.One of the main problems with previous endotracheal tubes was theannular ridge formed at the forward juncture of the inflatable sleeveand the dual-lumen tube. It is to this tube and inflatable balloon jointthat this invention relates.

SUMMARY OF THE INVENTION This invention overcomes the problems ofjoining a plastisol preformed inflatable balloon to a dual-lumenthermoplastic insertion tube to create a smooth sliding externalsurface. The inflatable plastisol sleeve or balloon of this invention isformed with an enlarged inflatable center portion and an elongatedforward collar portion. Rearwardly of the large center portion there isalso a rear collar portion. The dual-lumen tube is inserted in throughthe rear collar, the enlarged center portion and into the elongatedforward collar portion. Next, the forward collar and dual-lumen aresimultaneously out along a diagonal bias plane surface to develop anopen forward end of the endotracheal tube. Finally, the forward end ofthe endotracheal tube with the coterminous forward collar of the balloonand dual-lumen tube are heat fused in an induction heating die. Theendotracheal tube is then removed from the heating die to provide agenerally homogeneous rounded forward end portion of the endotrachealtube. There is no visible joint or ridge between the forward collar andthe insertion tube, but only a smooth sliding surface.

THE DRAWINGS FIG. 1 is a side elevational view of the endotracheal tubeshowing it complete and ready for attachment to an anesthesia machine;

FIG. 2 is an enlarged perspective view of the inflatable sleeve portionof the endotracheal tube;

FIG. 3 is a front elevational view showing a step in forming theplastisol inflatable sleeve with its elongated forward collar;

FIG. 4 is a side elevational view of the combined inflation sleeve andthermoplastic insertion sleeve showing how they are simultaneouslysevered at the elongated front collar portion; and

FIG. 5 is an enlarged. section view of the preformed inflationsleeve andthe dual-lumen thermoplastic tube immediately before they are assembled.

DETAILED DESCRIPTION Referring to these above-mentioned drawings, thecompleted endotracheal tube shown in FIG. 1 includes a dual-lumenthermoplastic insertion tube 1 that extends between a forward tipportion 2 and a rearward end 3. At rear end 3 is attached an adapter 4which connects with an elbow element 5. This elbow 5 is adapted toconnect directly to an anesthesia machine (not shown) that feedsanesthesia gas into the endotracheal tube at a precisely controlled rateand concentration.

Adjacent a forward end of the dual-lumen tube is an inflatable trachealballoon 6. This balloon extends from a forward tip 2 of the endotrachealtube, where it is integrally fused with the dual-lumen insertion tube,to a rear end 7 of the tracheal balloon. The tracheal balloon has apreformed enlarged central portion 8 that is spaced from the dual-lumentube 1 in its normal uninflated condition. To further inflate theenlarged central portion 8, air or liquid is injected through a valvemember 9, a pilot balloon l0, and through a side arm 11 that connects toan inflation lumen. This inflation lumen communicates with an interiorof the enlarged central portion 8 of the inflation sleeve. Thus, as airor liquid is forced in through the check valve 9 the center portion 8 ofthe tracheal balloon is inflated. The pilot balloon l0 likewise swellsand gives a visual indication that the enlarged central portion 8 isinflated. Pilot balloon 10 is outside the patient and readily visible atall times while inflated central portion 8 is in the patients tracheaand not readily visible.

In the perspective view of FIG. 2, the enlarged inflatable trachealballoon is shown in more detail. The endotracheal tube terminates in theforward tip portion 2 that extends rearwardly to a heel portion 12 ofthe endotracheal tube. This tip 2 and heel portion 12 lie along a biasplane surface at an annular lip 13 that surrounds an open forwardlyfacing end port 14. End port 14 communicates with a main lumen 15 thatextends longitudinally through the dual-lumen tube 1. Anesthesia gasentering through elbow connector 5 from an anesthesia machine passesthrough main lumen 15 and exits through forward port 14. If thephysician desires to suction the trachea and bronchial area of thepatient, he can readily insert a suction catheter or the like throughthe main lumen and cause it to protrude through forward port 14.

When the endotracheal tube is inserted into the trachea, the forward endportion includes open port 14 that can direct the anesthesia gas. Thereis also a side port 16 immediately forward of the enlarged centralinflatable section of the sleeve. Port 16 provides a safety port foranesthesia gases to exit should forward port 14 become clogged withmucos, etc. Also it is believed that ports 14 and 16 in FIG. 2 each helpdirect the anesthesia gases to the individual lungs.

In FIG. 2 there is also shown in dotted line the inflation lumen 17 thatcommunicates with the side branch tube 11. It is noted that thisinflation lumen 17 is closed off at a forward end portion 18. Also thisinflation lumen 17 includes a port 19 that connects the lumen 17 with aninterior portion of the inflatable enlarged central portion of thetracheal balloon. Therefore, the enlarged inflatable center section canbe inflated or deflated by means of a hypodermic syringe connected tocheck valve 9.

A very important feature of this invention is best illustrated in FIG.2, and includes the smoothly contoured external slide zone extendingfrom the forward angularly biased annular lip 13 to the enlargedinflatable central portion of the tracheal balloon. This smooth slidezone includes no abrupt interruption across the forward collar portionof the tracheal balloon.

The tracheal balloon and how it is formed is very critical to thisinvention. As shown in FIG. 3 the inflatable tracheal balloon is made bydipping a mandrel with an enlarged body segment conforming to thedesired internal contour of the inflatable enlarged central portion ofthe balloon. This mandrel 20 is dipped into a plastisol bath 21. Theplastisol begins to build up on the mandrel 20 until the desiredthickness of the balloon is obtained.

Next, the mandrel is removed from the polyvinyl chloride plastisol 21.The formed inflatable plastisol sleeve is then cured. Then, theinflatable sleeve is stripped from the mandrel and the preformed balloonhas an internal and external configuration shown generally in theenlarged cross-sectional view in FIG. 5. Here is shown the enlargedcentral portion 8 connected to an elongated forward collar 22 and arearwardly extending collar 23. The elongated collar 22 is closed at itsforward end and includes a small drip portion 24 formed when removingthe mandrel from the plastisol dip bath.

The dual-lumen thermoplastic tube is made from an extruded polyvinylchloride thermoplastic and a forward section is shown in FIG. 5. Herethe tube 1 includes an annular wall that defines a main lumen 14;located within wall 25 is a much smaller inflation lumen 17.

Having formed the inflatable plastisol tracheal balloon and thedual-lumen extruded thermoplastic tube, the two units are telescopicallyfitted together by inserting the dual-lumen tube 1 in through the rearcollar 23, enlarged inflatable section 8 and into forward collar 22.Preferably the collars 23 and 22 have an internal diameter slightlysmaller than the external diameter of the dual-lumen tube 1. This is sothe tracheal balloon will tightly grip the dual-lumen tube. If desiredthe collars 22 and 23 can be expanded over a tubular mandrel whileinserting tube 1 or they can be wetted with a solvent or lubricant.

When the dual-lumen tube 1 and inflatable sleeve 6 are assembled theyappear as in FIG. 4. The next step in the production of the novelendotracheal tube is to simultaneously sever both the forward collar 22and the tube 1 along a biased plane indicated at 28 in FIG. 4. Plane 28forms an angle in the range of 30 to relative to the longitudinal axisof the dual-lumen tube. This leaves both the forward collar 22 anddual-lumen tube 1 with coterminous biasly cut forward end surfaces.

At this time the two collars 22 and 23 can be permanently bonded withair tight joints to the dual-lumen tube 1 by heat fusion such as byinduction heating or bonded by solvent adhesive. Preferably the rear endportion of rear collar 23 is rounded and smoothly contoured to the tubeat this time. Also side port 16 can now be punched out of the wall ofthe insertion tube and the overlying tracheal balloons forward collar.

To form the smooth slide zone shown in FIG. 2 the combined tube 1 andinflatable sleeve section 6 are in-- serted into a heating mold. Thisfuses the forward tip into a thermoplastic mass which also fuses shutthe forward end 18 of the inflation lumen. When the endotracheal tube isfused, the forward collar 22 becomes integral and generally homogeneouswith the dual-lumen tube 1. This creates a smooth rounded forward lip 13and prevents delamination of the forward collar 22 and the wall 25 ofthe dual-lumen tube. It forms an externally smooth slide zone as shownin FIG. 2. There is no interruption at a forward end of the collar whereit joins to the dual-lumen tube. Thus the endotracheal tube can smoothlyslide past a patients vocal cords with reduced chance of injuring thevocal cords.

In the foregoing specification a specific embodiment has been used todescribe the invention. However it is understood by those skilled in theart that certain modiflcations can be made to this embodiment Withoutdeparting from the spirit and scope of the invention.

We claim:

1. In a medical endrotracheal tube comprising: a preformedtheremoplastic balloon with a permanently enlarged central portionintegrally connected by front and rear collars that respectively definefront and rear ends of the balloon; and a dual-lumen theremoplastic tubewithin and secured to each of the balloon collars, said central portionbeing spaced from said tube, the tube having a main lumen, an inflationlumen, and a port that connects the inflation lumen with the interior ofthe enlarged central portion of the balloon; means for providing forsafe insertion of the tube into a patients tracheal passage anddeterring inadverten trauma to the patient comprising said tube having afront end that terminates at the front end of the fron collar, anopening having a smooth annular reliever. edge lip portion, the combinedtube and overlying collars being homogeneously fused and forming asmooth continuous uninterrupted slide zone surface having a smoothseamless slide zone extending from the annular lip at the open forwardend of the tube to the central portion of the balloon so that the tubecan smoothl slide into the tracheal passage in a patient, said fusedforward ends of the collar and tube comprising a bonded homogeneous massof thermoplastic material for resisting delamination of the collar andthe dual lumen tube, the said enlarged central portion of thethermoplastic balloon and the dual lumen tube, in the normal uninflatedcondition, forming an annular space therebetween, said inflation lumenbeing fused shut at a forward end portion, forwardly of the inflationlumens communication with the enlarged central portion of the balloon.

2. The combination as set forth in claim 1 wherein the tube has alongitudinal axis and the forward end of the tube is biased at an anglerelative to this longitudinal axis.

3. The combination as set forth in claim 1 wherein the thermoplasticdual-lumen tube is of a plasticized polyvinyl chloride material.

4. The combination as set forth in claim 1 wherein the thermoplasticballoon is formed of a polyvinyl chloride plastisol 5. The combinationas set forth in claim 1 wherein the rear collar has its rearward endsmoothly rounded and blended into the exterior surface of the dual-lumenthermoplastic tube.

6. The combination as set forth in claim 1 wherein the forward portionof the medical tube includes a side port having a relieved marginthrough the combined front collar and dual-lumen tube into the mainlumen of this dual-lumen tube.

7. The combination as set forth in claim 1 wherein the dual-lumen tubeis an extruded thermoplastic polyvinyl chloride tube having a walldefining its main lumen and its inflation lumen is located in the mainlumen wall.

1. In a medical endrotracheal tube comprising: a preformedtheremoplastic balloon with a permanently enlarged central portionintegrally connected by front and rear collars that respectively definefront and rear ends of the balloon; and a dual-lumen theremoplastic tubewithin and secured to each of the balloon collars, said central portionbeing spaced from said tube, the tube having a main lumen, an inflationlumen, and a port that connects the inflation lumen with the interior ofthe enlarged central portion of the balloon; means for providing forsafe insertion of the tube into a patient''s tracheal passage anddeterring inadvertent trauma to the patient comprising said tube havinga front end that terminates at the front end of the front collar, anopening having a smooth annular relieved edge lip portion, the combinedtube and overlying collars being homogeneously fused and forming asmooth continuous uninterrupted slide zone surface having a smoothseamless slide zone extending from the annular lip at the open forwardend of the tube to the central portion of the balloon so that the tubecan smoothly slide into the tracheal passage in a patient, said fusedforward ends of the collar and tube comprising a bonded homogeneous massof thermoplastic material for resisting delamination of the collar andthe dual lumen tube, the said enlarged central portion of thethermoplastic balloon and the dual lumen tube, in the normal uninflatedcondition, forming an annular space therebetween, said inflation lumenbeing fused shut at a forward end portion, forwardly of the inflationlumen''s communication with the enlarged central portion of the balloon.2. The combination as set forth in claim 1 wherein the tube has alongitudinal axis and the forward end of the tube is biased at an anglerelative to this longitudinal axis.
 3. The combination as set forth inclaim 1 wherein the thermoplastic dual-lumen tube is of a plasticizedpolyvinyl chloride material.
 4. The combination as set forth in claim 1wherein the thermoplastic balloon is formed of a polyvinyl chlorideplastisol
 5. The combination as set forth in claim 1 wherein the rearcollar has its rearward end smoothly rounded and blended into theexterior surface of the dual-lumen thermoplastic tube.
 6. Thecombination as set forth in claim 1 wherein the forward portion of themedical tube includes a side port having a relieved margin through thecombined front collar and dual-lumen tube into thE main lumen of thisdual-lumen tube.
 7. The combination as set forth in claim 1 wherein thedual-lumen tube is an extruded thermoplastic polyvinyl chloride tubehaving a wall defining its main lumen and its inflation lumen is locatedin the main lumen wall.